System and method for treating biogas and wastewater

Abstract

The present invention relates to a system and method for treating wastewater, the method comprising the following steps: providing a container for receiving wastewater and gas, wherein the gas contains one or more constituent gas components; directing the wastewater and a first gas component of the gas to the container; lowering the temperature of the contents of the container from a first temperature to a second temperature to promote the formation of a clathrate hydrate containing the wastewater and the first gas component; raising the temperature of the contents of the container relative to the second temperature to promote the melting of the clathrate hydrate; and removing clean water and / or the first gas component from the container.

Description

Technical Field

[0001] The present invention relates to systems and methods for treating biogas and wastewater. In particular, but not exclusively, the present invention relates to treating biogas and wastewater from anaerobic digestion by forming nanobubbles and gas hydrates. The present invention also relates to treating multi-component mixtures. The present invention also relates to systems and methods for generating nanobubbles or nanodroplets. In particular, but not exclusively, the present invention relates to generating nanobubbles or nanodroplets without the use of electrolysis. Background Art

[0002] Anaerobic digestion (AD) is the conversion of biodegradable feedstocks such as animal waste, sewage, food waste, etc. into three main products: biogas, digestate, and water. The extraction of biogas is extremely desirable as it finds numerous applications in industry, especially in the generation of heat or electricity. However, the presence of H 2 S contaminants are highly corrosive and inhibit combustion, so significant purification of biogas is required before it can be effectively used. In addition, the disposal of waste products from anaerobic digestion without sufficient extraction of biogas such as methane and carbon dioxide is generally recognized to have negative environmental impacts, such as driving global greenhouse gas emissions. Existing purification methods such as pressure swing absorption, cryogenic separation, chemical scrubbing and membrane technology generally have significant capital and operating costs. In addition, existing purification methods are generally only cost-effective for large-scale biogas production, meaning that small-scale, localized solutions are not economically viable.

[0003] The digestate, which is the precipitate remaining after biogas extraction, can be used for fertilizer, compost, etc. However, the wastewater and digestate remaining after biogas extraction often contain pollutants or other undesirable contaminants, requiring treatment of the water output.

[0004] The value of nanobubbles to industry can be clearly seen in the multitude of applications found for them. Their high metastability in liquids finds nanobubbles popular for gas storage on a months-scale. Furthermore, their high surface area:volume ratio means they can be used in surface cleaning applications as they are able to adhere to insoluble dirt on surfaces. Nanobubbles are also found to be widely used in wastewater treatment by flotation and are also widely used in biogas applications, including controlling agricultural methane emissions.

[0005] This application has inspired a great deal of research into the various physical properties of nanobubbles and their production methods. For example, the cavitation effect, in which a sudden change in pressure in a liquid results in the formation of a low-pressure cavity, has been used to produce nanobubbles.

[0006] These methods have been found to be expensive in terms of energy requirements and the physical equipment required. In addition, some methods require additives in the process which contaminate the liquid while also producing relatively low gas solubility.

[0007] Published US patent application No. 2018141837 relates to a nanobubble and hydroxyl radical generator (NBHRG) and a treatment system for purifying water using NBHRG without chemicals. Published PCT patent application No. WO2005084786 relates to water containing oxygen nanobubbles and methods for producing the same. Published US patent application No. US20100147701 relates to a method and apparatus for applying an alternating electric field through a liquid to enhance disinfection performance. Published PCT patent application No. WO2017156410 relates to a method and apparatus for producing nanobubbles, wherein a gas is supplied to the apparatus under a certain pressure, forcing the gas to pass through a porous sidewall and form nanobubbles on the outer surface of a gas-permeable member. These technologies are based on methods such as: methods using water electrolysis, which is a process in which water is decomposed into hydrogen and oxygen, and the generated gas forms nanobubbles; and methods using hydrodynamic cavitation, which is a process of vaporization, bubble generation, and bubble implosion that occurs in a flowing liquid due to a decrease in local pressure and a subsequent increase in pressure. Methods involving electrolysis require direct hydroelectric contact of water with electrodes or discharge, or the introduction of another ion source. Alternatively, methods that do not use electrolysis, such as hydrodynamic cavitation, are believed to be less efficient in generating sustainable nanobubbles and result in reduced solubility enhancement.

[0008] To date, various methods related to the preparation of nanobubbles are known, however, such methods generally introduce electrolysis or foreign substances (such as ions) into the water in which the nanobubbles are generated, which may cause contamination. Published PCT patent application WO2014148397 uses water electrolysis, resulting in the decomposition of water into hydrogen and oxygen, wherein the generated gases form nanobubbles. Published PCT patent application WO2005084786 uses ultrasonic radiation and also uses added ions to stabilize nanobubbles. US20070189972, a patent application published in the United States, relates to a method for forming nanobubbles, the method forming nanobubbles by applying a physical stimulus to microbubbles contained in a liquid to cause the microbubbles to suddenly shrink. In addition, the method also involves the use of added ions. It is easy and energy-efficient to form a relatively large number of nanobubbles without microbubbles, and a higher gas solubility is obtained.

[0009] Published European patent application No. EP2986975 relates to a method and system for controlling nanobubble and nanoparticle dynamics in conical nanopores.

[0010] Therefore, there is a need for methods and systems for treating biogas and wastewater produced by anaerobic digesters that address at least some of the shortcomings of the prior art. In addition, there is a need for methods and systems for treating multi-component mixtures. In addition, there is a need for methods, systems and devices for generating nanobubbles or nanodroplets that address at least some of the shortcomings of the prior art. Summary of the invention

[0011] Therefore, a method for producing nanobubbles or nanodroplets is provided, the method comprising:

[0012] Providing a volume for containing a liquid;

[0013] dispensing a medium in the liquid;

[0014] An electric field is generated using electrodes near the volume region to promote the generation of nanobubbles or nanodroplets, wherein the electrodes and the liquid are not in direct electrical contact to prevent electrolysis from occurring within the volume region.

[0015] In one aspect, the medium is a gaseous medium. Advantageously, the gaseous medium comprises a mixture of two or more gases. Preferably, at least one gas is enriched.

[0016] In another aspect, the medium is a liquid medium. Advantageously, the liquid medium is a mixture of two or more liquid components. Preferably, at least one liquid component is enriched.

[0017] In one aspect, the liquid is an aqueous liquid.

[0018] In another aspect, the liquid comprises deionized water.

[0019] In an exemplary aspect, the electric field is a static electric field.

[0020] In another aspect, a cooling device is provided for cooling the contents of a volume region. Advantageously, the cooling device circulates a coolant around the volume region.

[0021] In one aspect, the method includes evacuating the volume region.

[0022] In another aspect, the method comprises agitating the contents of the volume. Advantageously, the agitation is provided by a rocking motion.

[0023] In an exemplary arrangement, the method includes: sensing temperature; and / or sensing pressure.

[0024] In one example, the volume of the liquid is about 20 cm 3Advantageously, a pressure of up to 100 bar is applied to the volume region. Preferably, a DC voltage of approximately 30 V is applied to the electrodes.

[0025] In one aspect, a sonic signal is applied to release nanobubbles or nanodroplets from a liquid.

[0026] In another aspect, a magnetic signal is applied to release nanobubbles or nanodroplets from a liquid.

[0027] In one aspect, the volume is cooled to a predetermined level to facilitate storage of the nanobubbles or nanodroplets within the body of liquid. Advantageously, the body of liquid is frozen.

[0028] In one exemplary aspect, a method for producing nanobubbles or nanodroplets is provided, the method comprising:

[0029] providing a volume area for containing a liquid;

[0030] dispensing a medium in the liquid;

[0031] An electric field is generated near the volume region to promote the generation of nanobubbles or nanodroplets, wherein no electrolysis occurs within the volume region.

[0032] The present invention also relates to a generator for producing nanobubbles or nanodroplets, the generator comprising:

[0033] A volume area, the volume area is used to contain liquid;

[0034] a source for supplying a medium to the volume for distribution within the liquid;

[0035] An electrode is used to generate an electric field near the volume region to promote the generation of nanobubbles or nanodroplets, wherein the electrode and the liquid are not in direct electrical contact to avoid electrolysis.

[0036] In one aspect, the source comprises a gas source for supplying a gaseous medium.

[0037] In another aspect, the source comprises a liquid source for supplying a liquid medium.

[0038] In another aspect, the electrodes are configured in a manner for providing a static electric field.

[0039] In an exemplary arrangement, the generator further comprises a cooling device for cooling the contents of the volume. Advantageously, the cooling device is configured in a manner for circulating a coolant around the volume. In one example, at least one portion of the generator defines a channel for containing a coolant therein.

[0040] In another aspect, a vacuum device is provided for evacuating the volume.

[0041] In another aspect, an agitation device is provided for agitating the contents of the volume region.

[0042] Advantageously, the agitation means comprises a mechanical agitator.

[0043] In one aspect, the electrodes comprise a cathode and an anode.

[0044] In another aspect, the cathode and anode are restricted from direct electrical contact with the contents of the volume to prevent electrolysis from occurring within the volume.

[0045] In one aspect, the cathode and anode are coated or covered with an electrically insulating coating or material.

[0046] In another aspect, the cathode and anode are arranged in a parallel configuration to provide an electric field having a strength that is inversely proportional to the distance between the cathode and the anode.

[0047] In another aspect, the electrodes comprise a plurality of anodes and a plurality of cathodes.

[0048] In another aspect, the electrode comprises a mesh construction. Advantageously, the electrode comprises a plurality of mesh elements.

[0049] In an exemplary arrangement, a plurality of anodes and a plurality of cathodes are arranged in a parallel configuration.

[0050] In one aspect, each mesh element comprises an aperture for receiving a portion of the delivery mechanism therein.

[0051] In another aspect, the delivery mechanism comprises an elongate tubular member for extending through the apertures of the mesh element. Advantageously, the tubular member is operably mounted on the base member.

[0052] In one aspect, the delivery mechanism comprises a plurality of outlets for facilitating the dispensing of the medium within the volume region. Advantageously, the outlets are sized to accommodate the medium passing therethrough but to prevent the ingress of liquid from the volume region.

[0053] In another aspect, the electrodes are arranged in a pattern consisting of a series of concentric elements.

[0054] In one aspect, the concentric elements can be constructed in such a way that each element consists of a cathode and an anode in contact.

[0055] In another aspect, an enricher is provided for use in enriching a medium.

[0056] In one aspect, a storage volume is provided to store nanobubbles or nanodroplets in a temperature controlled environment.

[0057] In another aspect, the nanobubbles or nanodroplets are frozen for storage.

[0058] The present invention also relates to a system for generating nanobubbles or nanodroplets, wherein the system comprises:

[0059] A generator comprising

[0060] A volume area, the volume area is used to contain liquid;

[0061] a source for supplying a medium to the volume for distribution within the liquid;

[0062] an electrode for generating an electric field near the volume to promote the generation of nanobubbles or nanodroplets, wherein the electrode and the liquid are not in direct electrical contact to avoid electrolysis; and

[0063] A control circuit is designed to control the generator.

[0064] According to one aspect, there is provided a method for treating wastewater, the method comprising the following steps:

[0065] providing a container for receiving wastewater and a gas, wherein the gas comprises one or more constituent gas components;

[0066] directing the wastewater and a first gas component of the gas to the container;

[0067] reducing the temperature of the contents of the container from a first temperature to a second temperature to promote formation of a clathrate hydrate comprising the wastewater and the first gas component;

[0068] increasing the temperature of the contents of the container relative to the second temperature to promote melting of the clathrate hydrate; and

[0069] Clean water and / or the first gas component are removed from the container.

[0070] In one aspect, the method further comprises generating nanobubbles of the first gas component.

[0071] In another aspect, directing the first gas component to the container comprises controllably releasing nanobubbles of the first gas component from a volume region. Advantageously, the volume region comprises a nanobubble generator. Preferably, controllably releasing nanobubbles of the first gas component comprises applying a signal to a liquid storing nanobubbles. In an exemplary embodiment, the signal comprises at least one of an acoustic signal or an electromagnetic signal.

[0072] In one aspect, the method further comprises removing the residue from the container.

[0073] In another aspect, the method further comprises: removing a second gas component of the gas from the generator. In one example, the first gas component comprises carbon dioxide or carbon monoxide. In one example, the second gas component comprises methane.

[0074] According to another aspect, there is provided a system for treating wastewater, the system comprising:

[0075] a container for receiving wastewater and a gas, wherein the gas comprises one or more constituent gas components;

[0076] means for directing said wastewater and a first gas component of said gas to said container;

[0077] A temperature control device, wherein the temperature control device is constructed as follows:

[0078] reducing the temperature of the contents of the container from a first temperature to a second temperature to promote formation of a clathrate hydrate comprising the wastewater and the first gas component; and

[0079] increasing the temperature of the container relative to the second temperature to promote melting of the clathrate hydrate; and

[0080] Means for removing clean water and / or said first gas component from the container.

[0081] According to another aspect, there is provided a system for processing a multi-component mixture, the system comprising:

[0082] a container for receiving a first medium and a second medium;

[0083] a source for supplying a first medium to the container and a source for supplying a second medium to the container;

[0084] A temperature control device for controlling the temperature of the contents of the container, wherein the temperature control device is configured to control the temperature of the contents of the container in a manner to promote the formation of a hydrate comprising a first medium and a second medium, and wherein the temperature control device is configured to control the temperature in a manner to promote melting of the hydrate to provide a first treated medium and a second treated medium.

[0085] In one aspect, the first medium comprises a gas, wherein the gas comprises one or more constituent gas components. Advantageously, the hydrate formed in the container is a clathrate hydrate.

[0086] In another aspect, the system further comprises a nanobubble generator for generating nanobubbles of the first gas component of the gas, and further comprises at least one conduit for connecting the volume of the nanobubble generator and the container therebetween.

[0087] In one aspect, a method for treating a multi-component mixture is provided, comprising:

[0088] providing a first medium to the container;

[0089] providing a second medium to the container;

[0090] controlling the temperature of the contents of the container to promote formation of a hydrate comprising the first medium and the second medium; and

[0091] The temperature of the contents of the container is controlled to promote melting of the hydrate, thereby providing a first treated medium and a second treated medium.

[0092] In one aspect, the first medium comprises a gas, wherein the gas comprises one or more constituent gas components.

[0093] In addition, the present invention relates to a method for releasing nanobubbles or nanodroplets from a liquid, the method comprising: controllably releasing the nanobubbles or nanodroplets by applying a signal to the liquid storing the nanobubbles or nanodroplets, wherein the signal comprises at least one of a sound signal or an electromagnetic signal. BRIEF DESCRIPTION OF THE DRAWINGS

[0094] The present invention will now be described with reference to the accompanying drawings, in which:

[0095] Figure 1 depicts a flow chart detailing a system for implementing the method of producing nanobubbles or nanodroplets according to the present invention;

[0096] Figure 2 An embodiment of a generator is depicted, including a cross section thereof, the cross section forming Figure 1 part of a system;

[0097] Figure 3 is a perspective view showing an exemplary embodiment of an electrode;

[0098] Figure 4 is a perspective view of another exemplary embodiment showing an electrode;

[0099] Figure 5 is a perspective view of another exemplary embodiment showing an electrode;

[0100] Figure 6 is a flow chart detailing exemplary steps for producing nanobubbles or nanodroplets;

[0101] Figure 7 is a graph showing the relationship between the surface area of ​​nanobubbles and their stability enhancement at various applied electric field strengths;

[0102] Figure 8 is a graph showing the relationship between nanobubble size and nanobubble lifetime;

[0103] Fig. 9 It is a graph showing the variation of the current of a DC power supply over a 24-hour period;

[0104] Fig.10 Yet another system for producing nanobubbles or nanodroplets according to the present invention;

[0105] Fig.11 A system for treating biogas and wastewater according to an embodiment of the present invention is shown;

[0106] Fig.12 is to show the use of the embodiment according to the present invention Fig.11 A flowchart of exemplary steps of a method for treating biogas and wastewater in a system;

[0107] Fig.13 is a flow chart showing exemplary steps of a method for treating wastewater;

[0108] Fig.14 is a flow chart showing exemplary steps of a method for processing a multi-component mixture. DETAILED DESCRIPTION

[0109] The present invention will now be described with reference to exemplary methods, generators and systems for treating biogas and wastewater produced by anaerobic digestion through the formation of nanobubbles and gas hydrates. It will be understood that the exemplary methods, generators and systems are provided to aid in understanding the present invention and should not be construed as limiting in any way. In addition, elements or assemblies described with reference to any one of the figures may be interchanged with elements or assemblies of other figures or other equivalent elements without departing from the spirit of the present invention. It will be understood that for simplicity and clarity of illustration, reference numerals may be repeated in the drawings to indicate corresponding or similar elements where deemed appropriate.

[0110] Referring to the drawings and first to Figure 1 and 2 , shows a system 100 for producing nanoelements according to the present invention, which nanoelements can be nanobubbles or nanodroplets. System 100 includes a generator 101 in which nanoelements are produced. Generator 101 includes a hollow interior region, which defines a volume region 102, which contains a liquid 103 therein. In an exemplary embodiment, liquid 103 can be deionized water or another aqueous solution. A medium in gas or liquid form is supplied to container 102 to be distributed in liquid 103. Provided as Figure 2The electrode 104 shown in the best figure is used to generate an electric field near the volume 102, thereby facilitating the production of nano-elements therein. The electrode 104 and the liquid 103 are not in direct electrical contact to avoid electrolysis in the volume 102. In an exemplary embodiment, the electrode 104 is covered or coated with an insulating material or coating or the like.

[0111] A cooling device such as a refrigerator or a constant temperature bath 105 is provided to cool the contents within the volume 102. The constant temperature bath 105 is constructed in a manner that a coolant circulates through at least a portion of the generator 101 near the volume 102. In an exemplary embodiment, the generator 101 is double-walled and has a channel 106, which is provided for accommodating the flow of a coolant therein. The coolant is introduced into the channel 106 through an inlet pipe 107. The coolant is then returned to the constant temperature bath 105 through an outlet pipe 108. Those skilled in the art will appreciate that there are a variety of cooling agents that can be used as coolants. For example, in an exemplary embodiment, the coolant is provided in the form of a mixture of water and ethylene glycol. Alternatively, the coolant can be an antifreeze. The constant temperature bath 105 is operable to supply a coolant in the temperature range of 263 to 343K.

[0112] The generator 101 also includes a sealing device for sealing the volume 102. The sealing device may include a closure 109 and a sealing gasket 110 for operably engaging with the side wall of the generator 102. In an exemplary embodiment, the sealing gasket 110 is made of Teflon. For example, a vacuum device for evacuating the volume 102 may be provided, which may be provided by a vacuum pump 111. An agitation device may be provided to agitate the contents of the volume. In an exemplary embodiment, the agitation device includes a mechanical agitator (not shown), which may be constructed in a manner to provide a rocking motion.

[0113] A data acquisition system 112 may be used to monitor parameters associated with the generator 101. A temperature sensor 113 is provided for sensing a temperature associated with the contents of the volume 102. In an exemplary arrangement, the temperature sensor comprises a thermocouple. A pressure sensor 114 is provided to sense a pressure associated with the generator 102. In one example, a platinum resistance thermometer (thermocouple) is used to monitor the temperature associated with the generator 102. The data acquisition system 112 is used to record the temperature monitored by the temperature sensor 113 and the pressure monitored by the pressure sensor 114 at intervals.

[0114] Generator 101 also includes a source 115 of a medium. In an exemplary embodiment, source 115 includes three separate gas sources that are selectively controlled to provide a suitable gas or combination of gases to volume 102. Figure 1Three gas sources are shown, propane, methane, and hydrogen, but those skilled in the art will recognize that any suitable gas source may be used and that the invention is not intended to be limited to the exemplary gases described. Generator 102 is controlled by control circuit 116. Control circuit 116 communicates with source 115, vacuum pump 111, temperature sensor 113, pressure sensor 114, data acquisition system 112, and constant temperature bath 105. Back pressure valve 117 facilitates controlled introduction of medium from source 115 to container 102 without loss of liquid 103 from volume 102. Inlet conduit 118 facilitates delivery of medium from source 115 to volume 102. Flow meter 119 is provided for metering the flow of medium to volume 102.

[0115] In use, the introduction of gas from the gas source 115 to the volume 102 is controlled via a series of ball valves 120, and will be described in more detail below. Control of the gas source 115 includes changing a series of ball valves 120 to deliver a gas or combination of gases to the vacuum pump 111 or a dump 121 as required. If the back pressure valve 117 is closed, the back pressure cylinder 122 accommodates the gas flow.

[0116] Figure 2 A cross section of a double-walled generator 101 is shown in detail, including a volume 102, in which a liquid 103 and a medium are loaded. In the exemplary embodiment, the liquid 103 is deionized water and has a 20 cm 3 Those skilled in the art will recognize that liquid 103 may include any suitable aqueous solution, and deionized water is provided by way of example. Figure 3 As best shown in FIG. 1 , the electrode 104 comprises a cathode 123 and an anode 124, which in an exemplary embodiment are placed in a parallel arrangement to the bottom of the volume 102 to generate an electrostatic electric field that is applied to the contents of the volume 102. The action of the electric field causes the formation and accumulation of nanobubbles of the gas medium or nanodroplets of the liquid medium inside the liquid 103. A direct current is applied to the electrode 104, generating a potential difference of up to 60V. The inventors have designed larger voltages in the practice of the present invention, which increase in direct proportion to other parameters used, such as the volume of liquid 103 and the medium introduced into the volume 102.

[0117] Importantly, an advantageous feature of the present invention is that none of the embodiments of the electrodes 104 are in direct electrical contact with the liquid-gas mixture, the electrodes having been coated or covered with an insulating coating or material or the like. Such an insulating coating may be, for example, a dielectric coating or other suitable material. Thus, the present invention differs from hitherto known electrolysis-based methods. Convenient, controlled and on-demand extraction of nanobubbles is performed by applying an acoustic signal, such as a sound pulse, to the contents of the volume 102 containing the nanobubbles. After applying the sound signal for a determined period of time, the nanobubbles or nanodroplets are completely extracted from the liquid 103, so that the volume 102 contains mainly liquid 103. This extraction method is not only sufficiently convenient and controllable, but also allows extraction over a period of time that far exceeds the metastability of the nanobubbles, which can extend to a time scale of several months. In addition, a magnetic field may be used for convenient, controlled and on-demand release of the nanobubbles. The magnetic field may be provided by a permanent magnet, but the inventors have contemplated other means, such as an electromagnetic pulse or a series of pulses. In addition, as described below with reference to Fig. 9 As described, this method of extracting nanobubbles of gas or nanodroplets of liquid medium is energy efficient.

[0118] Figure 3 A first generation embodiment of an electrode 104A is depicted, consisting of a cathode 123 and an anode 124 arranged in parallel and placed at a base 126 of the volume 102. Finite element studies performed by the inventors found that in this embodiment only 30% of the liquid 103 within the volume 102 was exposed to the electric field. Therefore, two more embodiments were developed.

[0119] Figure 4 A second generation embodiment of an electrode 104B is depicted that is comprised of concentric elements 127, each of which further comprises a cathode 123 and an anode 124 disposed in parallel contact at any given point on the concentric element 127. The cathode 123 and anode 124 are positioned through a central hole 128 to their respective electrical contacts. Figure 3 This embodiment provides for a greater degree of exposure of the liquid 103 to the electric field than the first embodiment shown, which is transported to the cavities between the concentric elements 127 .

[0120] Figure 5Describe the third generation embodiment of electrode 104C, wherein electrode 104 comprises a plurality of cathodes 123 and a plurality of anodes 124 arranged in a parallel configuration and connected to a plurality of mesh elements 129. Each mesh element 129 comprises a hole 130 for receiving a portion of a delivery mechanism 131, and the delivery mechanism 131 is used to deliver a gaseous medium or a liquid medium to the volume area 102. The delivery mechanism 131 comprises an elongated tubular member 132. The size of the elongated tubular member 132 is such that it extends through the hole 130 of the mesh element 129. In an exemplary embodiment, the elongated tubular member 132 is operably mounted on a base member 133. The elongated tubular member 132 and the base member 133 can be made of any suitable insulating material such as a specific polymer. The delivery mechanism 131 comprises a plurality of outlets 134, for promoting the distribution of the medium in the volume area 102. These outlets 134 are sized to accommodate the media but prevent the liquid 103 from entering the interior volume defined by the elongated tubular member 132 or the base member 133 .

[0121] The outlet 134 on the base member 133 is arranged relative to the mesh element 129 so that the medium introduced into the volume 102 from the source 115 will not be captured near the bottom of the volume 102 by the material line of the mesh element 129. The cross section 136 depicts the arrangement of the outlet 134 relative to the mesh element 129. In an exemplary embodiment, the outlet 134 extends radially from the tubular member 132 on the base member 133. The cathode 123 and the anode 124 are all individually connected to their own collector busbars on the opposite sides of the conductive mesh 31 to avoid undesirable short circuits. Compared with the previous embodiment, this embodiment of the electrode 104 increases the exposure level and electric field strength of the liquid in the electric field by ten times, and therefore, the inventor believes that this embodiment can also be expanded for industrial applications.

[0122] As shown in Table 1, the solubility levels of metastable gases achievable by this method are significantly higher than hitherto known. For methane, the gas solubility level was found to be 22.5 times the actual Henry's law for methane, while for oxygen, the gas solubility level was 2.5 times using this method. For carbon dioxide, the actual Henry's law coefficient was found to be increased by a factor of 15. The inventors believe that this has clear applications in the gas storage industry. The inventors also believe that this has important uses in reducing industrial carbon emissions.

[0123] Table 1 - Methane stored in water as bubbles

[0124]

[0125] In addition, the method can also be applied to a phase mixture (multiple gases or multiple liquids) in contact with a mother liquor, referred to as liquid 103 in the present invention. Although it should not be understood as limiting its scope, a possible realistic situation for this is a mixture of methane and carbon dioxide. The Henry's law coefficient solubility of carbon dioxide (in mg / l) is 30 times the Henry's law coefficient solubility of methane. Applying an electric field to such a mixture as in the method of the present invention will cause the solubility of carbon dioxide to increase by 12 times, so that a significantly larger portion of carbon dioxide will diffuse into the liquid compared to methane, thereby purifying methane to a level in the range of 97-98%. This has important applications, for example, in the biogas industry for controlling methane production in agriculture or for treating biogas from anaerobic digesters (for example in the wastewater treatment industry). Corrosive pollutants such as H, which may also inhibit combustion, can be removed. 2 S is removed, making it possible to use the biogas for the generation of heat and / or electricity, for example in a combined thermoelectric cycle.

[0126] Historically, methods for producing nanobubbles without electrolysis have been understood to be less energy efficient, however, the present invention is significantly more energy efficient than any prior art invention. From this perspective, the skilled person will understand that the present invention is of great value to the industry.

[0127] Reference now Figure 6 , Figure 6 A flow chart 150 is shown, which details exemplary steps for generating nanobubbles or nanodroplets according to the present invention. In step 154, a liquid is loaded into the volume 102. In step 156, a medium such as a gas medium or a liquid medium is dispensed into the liquid 103 in the volume 102. In step 158, an electric field is generated near the volume 102 to facilitate the generation of nanobubbles or nanodroplets using the electrode 104. In step 159, the electrode 104 and the liquid 103 are not in direct electrical contact to prevent electrolysis from occurring in the volume 102.

[0128] exist Figure 1 A schematic diagram of an exemplary arrangement according to the present invention is shown in FIG. 1 , which may be used to implement the steps of flowchart 150. It will be understood that it is not intended to limit the present invention to the particular generator 101 described herein, which is provided by way of example only. Generator 101 is provided as having a 340 cm 3The volume area 102 is balanced with a stainless steel (SS-316) volume, and the experiment is carried out using a maximum design pressure of 24 MPa. The temperature of the volume area 102 is controlled by circulating a mixture of water and ethylene glycol as a coolant in a constant temperature bath 105. The temperature of the constant temperature bath 105 can be adjusted within the range of 263 to 343 K. A platinum resistance thermometer (Pt-100) with an accuracy of 0.1 K is used to measure the temperature of the volume area 102. The use of a double-walled generator helps to control the temperature while the coolant does not contaminate the water 103. The thermometer is calibrated based on a reference platinum resistance thermometer. The pressure associated with the volume area 102 is monitored by a sensor 114 with an error of ± 0.010 MPa. An adjustable speed rocking device is used to perform mechanical agitation in the volume area 102. The system 100 is also equipped with a data acquisition program 112 to record the temperature and pressure at different time intervals. It will be understood that the exemplary values ​​described herein are provided only by way of example, and alternative values ​​can be used.

[0129] The cathode 123 and anode 124 of the electrode 104 are operably connected to a DC power supply having a potential of 30V. An electric field is applied to the water 103. The water 103 is loaded in a first step and then the volume 102 is sealed using a closing cap 109 and a sealing gasket 110. The generator 101 is loaded with 100 bar of gas and the pressure is recorded during the formation of nanobubbles or nanodroplets. Those skilled in the art will recognize that it is not intended to limit the invention to the exemplary values ​​described. For example, it is envisaged that the voltage of the DC power supply can be set to any desired value.

[0130] Before starting the process, the volume 102 is washed, cleaned and completely dried using an air stream; this serves to clean the volume 102 that will be loaded with the liquid and the introduced medium to avoid any contamination. Thereafter, the volume 102 is checked for leaks by injecting nitrogen at a pressure of 1 MPa. The leak test is to ensure the accuracy of the pressure readings during the nanobubble formation process. In the next step, an inert gas is purged and a vacuum pump 111 is used for about 30 minutes to evacuate the trapped gas from the volume 102. This second washing step with inert gas and gas evacuation removes any unwanted gas molecules within the volume defined by the volume 102. A volume of 20 cm 3Deionized water 3 is loaded into the volume 102; it is found that this volume of water 103 provides a good level of reproducible performance. The pressure associated with the volume 102 is increased by injecting a selected gas from a source 115 until the desired pressure is reached. In an exemplary experiment, about 100 bar of gas is loaded into the volume 102. After about 2 hours of gas-water contact in the presence of mechanical agitation, the water 103 is saturated. An adjustable speed shaking device (not shown) is used to increase the mechanical agitation in the volume 102. This mechanical agitation makes the water turbulent so as to better achieve water-gas contact, resulting in a higher bubble formation yield. Then, a direct current (0-60V) is applied while recording the pressure and temperature once per second. It will be understood that the exemplary values ​​described herein are provided by way of example only, and alternative values ​​can be used.

[0131] The formation mechanism of nanobubbles in an applied electric field was studied using molecular dynamics simulation and their stability conditions were characterized. Nanobubbles have been seen from the molecular dynamics of hydrate decomposition in an electric field. The inventors studied the stability of nanobubbles under an applied electric field and the results showed that the stability of hydrates is higher at higher field strengths, such as Figure 7 shown.

[0132] After the formation of methane nanobubbles, the solution was stored under ambient conditions (pressure, temperature) for three months and characterized using dynamic light scattering. The results showed that during aging, the nanobubbles merged together, resulting in an increase in bubble size, but this increase was not sufficient to force the nanobubbles to leave the aqueous medium, as shown in Figure 2. Figure 8 shown.

[0133] The energy of nanobubble generation during a 24-hour formation process can be calculated based on the energy stored inside the volume 102, where the combination of the electrode 104 and the water 103 can simulate a capacitor with a capacity of about 3 nF. During the nanobubble formation, the dielectric value of the water 103 changes, which can be considered as a capacitor leakage. In order to compensate for the leakage, additional energy must be added to the system 100. Therefore, in order to calculate the total energy, the applied current is recorded in the data acquisition system 112 during this formation process. Fig. 9 The graph shows the change in current over time. The observed current is very low, but the average value of this oscillation over 24 hours is 22nAmp, which means that 1.9 millicoulombs need to be added to the capacitor to maintain the same energy level. Therefore, the total energy for the formation of nanobubbles over 24 hours is:

[0134]

[0135] For only 20 ml of liquid 103, this is a very small amount of energy supplied, which indicates a significant level of energy efficiency. This can be understood by comparison with currently available systems in the wastewater industry, for example. The energy consumption of the present system 100 is 0.3 Whr / m of water 103. 3 This is much lower than the energy consumption achieved by existing advanced systems in the wastewater industry (40Whr / m 3 ). In addition, aeration levels in the wastewater industry currently reach a limit of about 0.5 mg / l dissolved oxygen, while the method of the present invention reaches levels of 25-30 mg / l. In addition, the aeration levels achieved in the present invention are metastable on a time scale of several months. It will be understood that the exemplary values ​​described herein are provided by way of example only, and alternative values ​​may be used.

[0136] The key parameters in the method according to the invention are:

[0137] Field strength (at Figure 3 In the electrode design, E = V / d)

[0138] where V is the applied voltage; and

[0139] d is the distance between the cathode and the anode in the electrode design.

[0140] When using the first generation electrode 104A, 30V is applied to produce a relatively high field strength. Those skilled in the art will appreciate that it is not intended to limit the applied voltage to 60V, as other values ​​may be applied. The distance d between the cathode and the anode is 5 mm. Thus, the maximum applied field is 12000 V / m. This d value is Figure 4 The second generation electrode 104B and Figure 5 The third generation electrodes 104C may be different, so the field strength will vary accordingly. The distribution is primarily a function of the electrode geometry and design.

[0141] Typically, the kinetic energy of the molecules is reduced, so that the nanobubbles are more relaxed, resulting in a faster bubble formation process. On the other hand, extremely low temperatures can cause certain adverse reactions, such as the formation of hydrates in the case of freezing of methane or water. As a result, the inventors chose 15°C for methane (lower than 13°C for the formation of methane hydrates) and 2°C for oxygen.

[0142] To accelerate the formation of nanobubbles, the inventors realized that more gas molecules need to be in contact with the water 103. This is achieved by increasing the gas pressure within the volume 102. In an exemplary arrangement, the volume 102 is loaded with 100 bar of gas. The inventors realized that this pressure can be significantly reduced by changing the purge system or by adding a pre-saturation step using an enricher.

[0143] refer to Fig.10, shows another system 200 for generating nanobubbles or nanodroplets, also in accordance with the present invention. System 200 is substantially similar to system 100, and similar elements are indicated by similar reference numerals. The main difference between system 200 and system 100 is that system 200 includes an enricher 205 for enriching the gas medium. The inventors realized that performance could be optimized by increasing gas absorption if it resulted in a higher metastable gas capacity remaining for a much longer period of time exceeding several months when the electric field is removed and the pressure is reduced. It is in 2 3 T, P and electric field strength in DoX factorial design. For example, one can use 40 and 160 bar, 1 and 35 °C, and (estimated) electric field strengths of 5000 V / m and 20000 V / m to develop a regression fit etc. in a series of 8 experiments for the following two dependent variables: dissolved gas level in the tank under electric field and P conditions; secondly, dissolved gas level (mg / l) within a few hours after removal from pressure volume 102 and storage at ambient pressure in the laboratory.

[0144] Storage container 210 can be used to store nanobubbles / nanodroplets. In system 200, storage container 210 is at 3-4°C, which slows down the cavitation and aggregation of reverse nanobubbles to micron size (and escape to the gas phase). However, for long-term storage (months), or for transporting liquid containing nanobubbles, the water containing nanobubbles is directly frozen after being taken out of volume area 102 to store the nanobubbles in water for a long time. It is then thawed for later use.

[0145] It is noteworthy that freezing the liquid (containing nanobubbles) at high pressure while still in volume 102 will enable a storage time of much higher levels of actual gas solubility to be achieved. For example, in ice it is possible to achieve, for example, 0 2 If it can be stored in cheap commodity ~25 bar pressure drums (e.g. plastic, Al) that are commonly / conventionally used in the process industry for medium pressure storage during transport, it can be kept in such containers in ordinary industrial / consumer refrigerators in a very economical manner for long-term storage and transport with significantly increased gas content, and then used in other applications after thawing in a higher pressure grade container.

[0146] Acoustic and / or magnetic field exposure can be used to extract nanobubbles or nanodroplets to provide controlled, on-demand release. By exposing the storage volume 210 to acoustic pulses of about 10-50N, it can be seen that nanobubbles of gas or nanodroplets of liquid essentially leave the metastable liquid in hours rather than weeks or months. The inventors have also recognized that magnetic fields can be used to provide controlled release of nanobubbles or nanodroplets from water. A permanent magnet or an electromagnetic pulse or a series of such pulses can be used to provide the magnetic field. The field strength can be on the order of millitesla or higher.

[0147] The differential absorption of species in aqueous nanophase fluids (whether droplets or gases, depending in part on the prevailing temperature and pressure relative to their respective species-specific critical points) is an important fundamental feature to manipulate in order to better utilize nanophases as reagents for species separation processes.

[0148] The development of nanophase enhanced gas-liquid absorption operations is used / advantageous for classical gas-liquid absorption in packed columns for various purposes and applications, such as compliance with air quality standards in terms of gas emissions, or indeed liquid-liquid extraction operations. Advantageously, the usual gas-liquid equilibrium constant of the form y i =H i x i (where H i is Henry's law constant, HLC) can be used Instead, is the enhanced actual HLC due to the additional accommodation of the nanophase. (Given that the time scale for this metastable state exceeds months and is much shorter than the residence time of the unit operation, this is considered a practically valid working approximation.) Therefore, the inventors relied on "equilibrium" conditions to retain the corpus for process-engineering design analysis of the unit operations.

[0149] The significantly greatly improved surface area to volume ratio in the nanophase, coupled with more favorable actual equilibrium conditions, will easily design and study more effective multi-component gas separation / enrichment operations than those currently available on the market. Although this concept of the present invention can be applied to pure gas stripping, it is also of great value for differential absorption of multi-component gas mixtures in the gas phase and dissolved in an immiscible liquid phase (e.g., biogas purification and flue gas treatment as described below). In a specific embodiment, for process control purposes (i.e., proportional control of gas composition), it is possible to use an online gas chromatography system to confirm the gas enrichment level on a near real-time basis. Combined molecular dynamics simulations show the microscopic mechanism of absorption of multi-component gas mixtures in liquids, which will contribute to further process optimization.

[0150] In certain embodiments, this principle can be further applied to distillation, whether single or multiple components. In addition, for nanobubble-enhanced gas-liquid operations, the "NB moving balance" can be used. in is an enhanced actual HLC due to the additional accommodation of the nanophase. In preliminary process simulation results with this shifting equilibrium relationship, much lower energy consumption (about 40%) was achieved, and the gas phase enrichment of the most volatile component (MVC) was greatly improved relative to conventional distillation.

[0151] Here, in a preliminary "pre-NB" operation, depending on the flue gas composition, a pressure swing adsorption (PSA) type process can be used to remove higher CO 2 concentration, especially if %CO 2 Above about 10-12%, as it is usually in flue gas emissions from steel mills and cement plants and power plants or CHP plants (whether in biogas or any other part). Now, once PSA can be used for higher CO 2 Flue gas treatment to remove CO 2 “major initiatives”, “low hanging fruit” or “marginal CO removal with economic / operational benefits” 2 treatment”, we have the prospect of NB-enabled differential flue gas stripping / removal.

[0152] In an advantageous embodiment of the invention, the flue gas is enriched by passing the (residual) flue gas directly through water, for example by means of an ejector or a Venturi-type nozzle, with the formation of a portion of preliminary microbubbles and then of active nanobubbles / droplets as described above. 2 and N 2 Almost disappeared, in terms of water concentration, slightly above the HLC level (no more than ~2.5 times). This may greatly increase the solubility limit of other (contaminant) gases.

[0153] In another embodiment of removing gaseous components from flue gases, a bidirectional liquid / gas chamber separated by a plane containing carbon nanotubes (or any other hydrophobic porous solid network that prevents water from flowing from one side to the other) can be used. Initially, the "empty" side of the bidirectional box can have a vacuum applied by a vacuum pump so that the absolute pressure on this side is about 0.3-0.5 bara. Preferably, the pressure on this side of the bidirectional box has a pressure of less than 1 bara. The liquid water (containing NB or nanodroplets) is on the other side of the bidirectional box. Then, the (polluted, hydrophobic) gas (such as CO, CO 2, methane, ammonia, etc.) are transferred to the gas side through carbon nanotubes because their chemical potential drives them through the gas phase, while carbon nanotubes do not allow water to pass through to any appreciable extent.

[0154] In an embodiment similar to that described above with respect to the removal of gaseous components from flue gas, direct air capture (DAC) may be implemented. Unless desired, the PSA-type method steps described above are not particularly required as preliminary steps. It is contemplated that in addition to "ambient air", the generation of nanobubbles and hydrophobic or carbon nanotube filtration based on blocking / rejecting water passage can also be used in other embodiments. More specifically, "ambient air" or DAC herein refers to air indoors or outdoors, but the key is that it is at or near ambient pressure. However, it is contemplated that in addition to the dedicated CCS-type system for point emitters described above, it can also be applied to air in (seasonal or year-round) farming such as indoor battery farming (with elevated methane levels or ammonia levels, etc.) and DAC, especially in cities and surrounding areas. Further applications of these embodiments may include, but are not limited to, crop growth, irrigation, hydroponics, fish farms and aquaculture. It will be understood that DAC is also considered to be highly desirable as part of efforts to mitigate climate change and in pollution prevention and control, particularly in urban and industrial environments. Likewise, any such improvements to the DAC method and system are widely understood to be advantageous.

[0155] Advantageously, for mixtures of immiscible liquids, the liquid-liquid equilibrium-partition relationship is of the form x i,k =K i,j,k x i,j (where K i,j,k is the liquid-liquid partition coefficient of species j relative to species k in liquid phase i) can be used (in is an enhanced actual distribution coefficient due to additional preferential accommodation in one phase) substitution. In experiments with immiscible liquids, it has been observed that the generation of nanodroplets to varying degrees in each liquid phase results in a significant enrichment of species in one liquid phase. This is a distinctly advantageous aspect of the present invention and an important unit operation in the chemical industry. Advantageously, in certain embodiments, using the nanodroplet formation method described above, multicomponent petroleum nanodroplets can be used as a means of enriching species concentrations of petroleum fractions in water. In utilizing In simulations of , a large concentration of oil nanodroplets in water has been observed. It is envisioned that such applications will be useful for revisiting mature oil wells.

[0156] Another advantageous application of the exemplary generator, system and method for producing nanobubbles is in an agricultural environment. Specifically, but not exclusively, the exemplary generator, system and method for producing nanobubbles or nanodroplets can be used to enhance seed germination. Enhancing seed germination brings many benefits to crop growth productivity in agriculture, animal feed and biofuel production. As discussed, in various embodiments using the exemplary generator, system and method, water with a large amount of absorbed desired gas can be obtained. In certain embodiments, the gas can be oxygen. Advantageously, using the exemplary generator, system and method, the water can contain dissolved oxygen levels as high as 25-30 mg / l. For example, an experiment was conducted to test the effectiveness of strongly oxygenated water in enhancing the germination of watercress seeds. Five to six watercress seeds were placed in a 24-slot tray; about 70 ml of peat moss was placed in each slot. About 15 ml of deionized water was provided to each slot of the first tray, and 15 ml of deionized water with about 15 mg / l dissolved oxygen (mostly in the form of nanobubbles) was provided to each slot of the second tray. After a period of 7 days, the two trays were compared and it was found that in the tray with deionized water containing nanobubbles, the seed germination growth was improved by about 35% compared to the tray containing deionized water without nanobubbles. Therefore, another advantageous aspect of the generator, system and method for producing nanobubbles of the present invention is its utility in enhancing crop growth. It will be understood that the example of watercress seed germination is provided only as an example and should not be construed as limiting in any way, shape or form. The liquid containing nanobubbles produced according to the present invention can be applied to various liquids and gases and varied in different proportions according to the needs of the user. For example, it is contemplated that in addition to private use, the volume of liquid and gas used in the production of nanobubbles can also be adjusted on an industrial scale. Advantageously, the liquid water to be enriched with DO can be placed in direct contact with the atmosphere and then the nanobubble generation process can be carried out. This can be achieved by retrofitting open water (sedimentation) tanks and reservoirs to a larger "grid" scale.

[0157] Advantageously and similarly to the above embodiments with respect to gas-liquid absorption and liquid-liquid extraction, the solid-liquid equilibrium-partition relationship is of the form k =K j,k x j (where K j,k is the solid-liquid partition coefficient of species j in the solid phase relative to species k) available (in is an enhanced actual distribution coefficient due to the substitution of the otherwise preferential accommodation as nanobubbles or nanodroplets in the liquid phase. In experiments, it has been observed that the generation of nanodroplets or nanobubbles in the liquid phase to varying degrees achieves the enrichment of a large number of species in the liquid phase. Solid-liquid leaching is a very important unit operation in the mining and quarrying industries. The resulting wastewater with enhanced mineral and dissolved ionic species can be characterized according to the concentration of the respective Fig.11 and 12 The system and method best described in the present invention is to treat / clean by forming hydrates. As previously mentioned, if desired, O 2 -Nanobubble-enhanced activated sludge further cleans the remaining water.

[0158] In another advantageous embodiment of the invention, a stoichiometric excess of H 2 In the form of nanobubbles, the production of nanobubbles can be used in the anaerobic digester to obtain “grid quality” pure biogas such as biomethane without subsequent purification. As will be discussed below, the generation of nanobubbles can also be used in the AD step itself for H 2 S and CO 2 The need for subsequent biogas purification is therefore largely redundant, providing a further improvement over prior art anaerobic digesters. The excess hydrogen in the AD step enables it to produce more pure biogas / biomethane while reducing CO 2 and H 2 S. H in the form of nanobubbles 2 Higher levels of methane purity can be achieved, meaning less biomethane enrichment is required (this can still be achieved according to the following Fig.11 and 12 to accomplish the system and method described in ).

[0159] Reference now Fig.11 , a flow chart of an exemplary system 1100 for treating a multi-component mixture is shown. In an exemplary embodiment, the system 1100 may include the exemplary generator 101 of the previous figures, however other sources of nanobubbles or nanodroplets are considered feasible, and in various embodiments, it is optional and advantageous to generate the nanophase components on site. In an exemplary embodiment, the system 1100 may be used to treat biogas and wastewater produced by an anaerobic digester via the formation of nanobubbles and gas hydrates. However, the exemplary system 1100 is not limited to use in anaerobic digestion, and it is envisioned to be used for other purposes.

[0160] The operation of the system 1100 will now be described with respect to an exemplary method of treating wastewater from an anaerobic digester, however, it is noted that wastewater is an example of a first medium, and a gas such as biogas is an example of a second medium. Moreover, the source of the first medium and / or the second medium need not be an anaerobic digester, as will be appreciated in view of, for example, the various embodiments described above.

[0161] Wastewater may be introduced into the generator 101 through a first inlet 1105, and biogas may be introduced into the generator 101 through a second inlet 1110. The wastewater may optionally be directed through a sand filter 1115 prior to reaching the generator 101 to minimize the volume of particulate matter or other undesirable materials other than the wastewater itself that reaches the generator 101. Once the biogas and / or wastewater are provided to the generator 101, a biogas purification process may be initiated. In an exemplary embodiment, the biogas purification process is such as according to Figure 6 Advantageously, such as Figure 6 The biogas purification process of the biogas purification process can be completed once, that is, methane with a purity of up to 98% can be obtained, so it may not be necessary to repeat the purification process. In an exemplary embodiment, the microorganisms may be H 2 S is converted to precipitate sulfur; in the case of iron addition, it is converted to FeSO 4 By forming CO 2 Nanobubbles from CO 2 Purified CH 4 The gas can be transported from the generator 101 to the gas storage unit 1125 via the first outlet 1120. In an exemplary embodiment, the gas storage unit 1125 comprises a plurality of gas storage containers. 2 Nanobubbles may be released from the generator 101. In an exemplary embodiment, CO is controllably released from its solvated nanobubble form in the generator 101 by applying an acoustic or electromagnetic signal, as described above. 2 . Wastewater and CO 2 The wastewater is directed to the secondary treatment vessel 1130 via the first outlet 1135. As an alternative to directing the wastewater to the generator 101, an outlet (not shown) may be provided at the generator 101 that is connected to a conduit that directs the wastewater to the secondary treatment vessel 1130. The outlet may be connected to the conduit by a tap or a controlled release mechanism such as a valve mechanism (not shown).

[0162] It will be understood that although the present figure shows three copies of the secondary processing vessel 1130, this is presented for illustration purposes only to clarify the three-stage process occurring in the secondary processing vessel 1130. This three-stage process will now be described.

[0163] In the first stage, wastewater and CO 2 is loaded into secondary treatment vessel 1130. In an exemplary embodiment, the wastewater and CO 2 Load into processing vessel 1130 at room temperature.

[0164] In the second stage, the secondary process vessel 1130 is cooled to a temperature less than the loading temperature of the first stage. 2 The clathrate hydrate is formed with the wastewater. The formation of the clathrate hydrate significantly purifies the wastewater. The residual dirt that has been separated from the water can then be directed out of the secondary treatment vessel 1130, leaving behind the CO 2 and clean water.

[0165] In the third stage, the temperature of the secondary treatment vessel 1130 may then be increased to promote melting of the clathrate hydrate. Clean water may then be directed out of the secondary treatment vessel 1130 via a second outlet 1140. In one embodiment, the clean water may be directed to a water storage vessel (not shown), such as, but not limited to, a water storage tank or a cellar. The water storage vessel may be used for temporary or long-term storage of water. In another embodiment, the clean water may be directed to a public or private water supply. The CO may be removed via a third outlet 1145. 2 Lead to the gas storage container of the gas storage unit 1125.

[0166] Fig.12 Is displayed using Fig.11 A flowchart of an exemplary method 1200 for processing a multi-component mixture by an exemplary system 1100 of FIG. Figure 6 In one embodiment, the liquid provided to the generator 101 in step 1210 comprises entirely wastewater. In an alternative embodiment, the liquid provided to the generator 101 in step 1210 comprises in part wastewater and in part other liquids in addition to wastewater. In another embodiment, the liquid provided to the generator 101 does not comprise any wastewater, and wastewater is provided directly to the secondary treatment vessel 1130 from an anaerobic digester or another source. Typically, the wastewater will be received from an anaerobic digester, however, it will be understood that other sources of wastewater, such as, but not limited to, sewage, are equally feasible. For example, using Fig.11 and Fig.12The wastewater purified by the system and / or method may include, but is not limited to: seawater, fracking water, reverse osmosis wastewater, agricultural wastewater, slaughterhouse and tannery wastewater, mining wastewater, and cement and construction wastewater. In addition, the source of the gas does not necessarily have to come from the anaerobic digester - by way of example only, the gas can come from a landfill, a mine, a building, an industry, a vehicle, or other location. In fact, the embodiment of the anaerobic digester is provided by way of example only; the application of nanobubbles or nanodroplets of guest species such as gases to form hydrates with wastewater components and treat wastewater can be applied to various wastewater treatment schemes. Indeed, the comprehensive purification of multi-component gas and wastewater streams can be designed to be widely applicable to a variety of different scales of sites other than anaerobic digestion, from small agricultural or household uses to large-scale industrial applications such as chemical processing or production plants. As previously described, the medium supplied to the generator 101 can be a mixture of two or more gases. In an exemplary embodiment, the gas medium supplied to the generator 101 in step 1210 contains at least methane and carbon dioxide. Furthermore, as described above, the generator 101 may also be used to form nanodroplets, and the same nanodroplets may be used in Fig.12 In the above process and Fig.11 In the system 1100 of methane. Gas components other than methane may include, but are not limited to, propane, ethane, butane, pentane, hexane, etc., and their isomers such as isobutane (if desired). In embodiments where the multi-component mixture involves multiple liquids, hydrates containing liquids and not necessarily gases may be formed.

[0167] The formation of nanobubbles (or nanodroplets or some combination) of the second gas substantially purifies the first gas. In an exemplary embodiment, the formation of nanobubbles of the second gas can purify the first gas to about 98%. Once the purification of the first gas is completed according to the exemplary steps present in step 1210, the purified first gas can be removed 1220 from the generator 101. In an exemplary embodiment, the purified first gas can be directed to a gas storage unit 1125. In an exemplary embodiment, the first gas component is methane.

[0168] In an exemplary embodiment, the medium supplied 156 to the volume of the generator 101 is a multi-component gas. Figure 6The multi-component gas may be separated 1210 by a step of separating 1210 the multi-component gas, and the purified first gas component may be optionally directed out of the volume of the generator 101. After removing 1220 the purified first gas, the second gas component of the medium (now in the form of solvated nanobubbles as a result of step 1210) may be controllably released 1230 from the generator 101. In addition to the second gas component of the medium, a second medium, which in the exemplary embodiment is wastewater, may also be directed to the secondary treatment vessel 1130. The wastewater may be directed from the volume of the generator 101 or directly from a source. The source of the wastewater may be the same or different from the source of the first medium. In the exemplary embodiment, the source of the wastewater and the first medium is an anaerobic digester. In the exemplary embodiment, the controlled release of the second gas component from its nanobubble form may be implemented according to the previously described release method, in which sound or electromagnetic signals are applied to the generator 101. In the exemplary embodiment, the second gas component that forms the nanobubbles may be carbon dioxide, and the purified component directed out of the volume of the generator 101 may be methane.

[0169] After step 1230, the nanobubbles of the second gas and the wastewater may then be directed 1240 to a temperature maintained at the first temperature T 1 In the exemplary embodiment, the first temperature T 1 is room temperature or at about 293 ≤ T 1 It will be appreciated that the temperatures herein are given in the SI base unit of Kelvin (K).

[0170] The temperature of the secondary processing vessel 1130 may then be reduced 1250° to a temperature T 2 <T 1 In an exemplary embodiment, the temperature T 2 in the range of about 273K to 283K. Subsequently, 1260 inclusion hydrates began to form from the second gas and the wastewater, substantially purifying the wastewater. Inclusion hydrates are non-stoichiometric crystalline inclusions in which a hydrogen-bonded water host lattice encapsulates small guest molecules in cavities. Hydrates have become very important for treating (heavily contaminated) water because they can form stoichiometrically pure crystals with the introduced gas and separate from the residual sludge by flotation. In order for hydrate crystallization to be effective, the gas and water need to be in close contact. Obviously, the use of a nanophase (whether in the form of bubbles or droplets, or some combination) will increase the concentration of water, especially for liquid nanodroplets, and increase the contact area. For example, so far, in studies of propane nanodroplets and about 4 wt% (solids) wastewater, the rate of hydrate formation has been about twice the rate of hydrate formation without a nanophase in a pressure vessel system, and additionally for CO 2In molecular dynamics (MD) simulations of nanodroplets, the inventors also witnessed a significant increase in the hydrate formation rate due to the supersaturation of the aqueous guest.

[0171] The residual foulant, now separated from the wastewater due to the formation of gas-hydrates, is removed 1270 from the secondary treatment vessel 1130. In certain embodiments, the residual foulant may be transferred to a waste holding unit. The residual foulant may find subsequent use in industry or elsewhere, such as as a feedstock.

[0172] After the residual foulant is removed from the secondary processing vessel 1130, the temperature of the secondary processing vessel 1130 may be increased 1280. In an exemplary embodiment, the temperature of the secondary processing vessel 1130 is returned to room temperature, or at about 293 ≤ T 1 (K)≤298. By comparing with T 2 At elevated temperatures, melting of the clathrate hydrate may occur. One or both of the second gas and clean water may then be removed 1290 from the secondary treatment vessel 1130.

[0173] Fig.11 and 12 The systems and / or methods may have a variety of applications together or separately. Advantageously, there are a variety of small-scale applications that are significantly more economically viable than the prior art. By way of example only, Fig.11 and 12 The systems and / or methods can be used in agricultural environments including small-scale agricultural environments, such as farms with small numbers of livestock or late-cut silage / beat. In such embodiments, in addition to wastewater treatment, the methods of purifying biomethane or other gases according to the above-described methods and systems can also promote self-sufficient production of biomethane or other gases to support household and dairy operations, transportation (e.g., cars, tractors, etc.).

[0174] refer to Fig.13 Flowchart 1300, the Fig.13 Exemplary steps of a method for treating wastewater according to the present invention are shown. In step 1305, a container for receiving wastewater and gas is provided, wherein the gas comprises one or more constituent gas components. In step 1310, the wastewater and the first gas component of the gas are directed to the container. In step 1315, the temperature of the contents of the container is reduced from the first temperature to the second temperature to promote the formation of a clathrate hydrate comprising the wastewater and the first gas component. In step 1320, the temperature of the contents of the container is increased relative to the second temperature to promote the melting of the clathrate hydrate. In step 1325, clean water and / or the first gas component are removed from the container.

[0175] refer to Fig.14 Flowchart 1400, the Fig.14 Exemplary steps of a method for processing a multi-component mixture are shown. In step 1405, a first medium is provided to a container. In step 1410, a second medium is provided to the container. In step 1415, the temperature of the contents of the container is controlled to promote the formation of a hydrate comprising the first medium and the second medium. In step 1420, the temperature of the contents of the container is controlled to promote melting of the hydrate to provide a first processed medium and a second processed medium.

[0176] It will be appreciated by those skilled in the art that various modifications may be made to the above-described embodiments without departing from the scope of the present invention. It will be appreciated by those skilled in the art that the operation of the system has been described with reference to specific values ​​such as pressure, temperature, voltage, volume provided only by way of example, and it will be appreciated that alternative values ​​may be used. For example, values ​​may vary when scaling or modifying the experimental setup within the scope of the present invention. In addition, it will be appreciated by those skilled in the art that not using additives and / or electrolysis in the exemplary embodiments is indeed only exemplary. In this way, it will be appreciated that, according to the appended claims, only when deemed necessary, the subject matter is limited.

[0177] Similarly, when used in the specification, the word "comprising" is used to specify the presence of stated forms, integers, steps or components, but does not exclude the presence or addition of one or more other forms, integers, steps, components or groups thereof.

[0178] It will be appreciated that while exemplary features of an apparatus for generating nanobubbles / nanodroplets and treating biogas and wastewater have been described, such an arrangement should not be construed as limiting the invention to such features. The method of generating nanobubbles / nanodroplets and treating biogas and wastewater may be implemented in software, firmware, hardware, or a combination thereof. In one mode, the method is implemented in software as an executable program and is executed by one or more special or general-purpose digital computers such as personal computers (PCs; IBM compatibles, Apple compatibles, etc.), personal digital assistants, workstations, minicomputers, or mainframe computers. The steps of the method may be implemented by a server or computer in which a software module resides or partially resides.

[0179] Typically, with respect to hardware architecture, as will be readily appreciated by those skilled in the art, such a computer will include a processor, a memory, and one or more input and / or output (I / O) devices (or peripherals), which are communicatively connected via a local interface. As known in the art, a local interface can be, for example, but not limited to, one or more buses or other wired or wireless connections. A local interface can have other elements such as a controller, a buffer (cache), a driver, a repeater, and a receiver to enable communication. In addition, a local interface can include address, control, and / or data connections to enable appropriate communication between other computer components.

[0180] The processor can be programmed to implement the functions of the method for controlling a generator of nanobubbles / nanodroplets, and more generally the functions of the system for treating biogas and wastewater. A processor is a hardware device for executing software, particularly software stored in a memory. The processor can be any custom or commercially available processor, a main processing unit (CPU), a secondary processor among multiple processors associated with a computer, a semiconductor-based microprocessor (in the form of a microchip or chipset), a macroprocessor, or any device generally used to execute software instructions.

[0181] The memory is associated with one or more processors and can include any one or combination of volatile storage elements (e.g., random access memory (RAM, such as DRAM, SRAM, SDRAM, etc.) and non-volatile storage elements (e.g., ROM, hard drive, tape, CDROM, etc.). In addition, the memory can incorporate electronic, magnetic, optical and / or other types of storage media. The memory can have a distributed architecture in which various components are remote from each other but can still be accessed by one or more processors.

[0182] The software in the memory may include one or more separate programs. A separate program includes an ordered list of executable instructions for implementing logical functions to implement module functions. In the above example, the software in the memory includes one or more components of the method and can be executed on an appropriate operating system (O / S).

[0183] The present invention may include components provided as: source programs, executable programs (object code), scripts, or any other entity containing sets of instructions to be implemented. When it is a source program, the program needs to be transcribed by a compiler, assembler, interpreter, etc., which may or may not be included in the memory, in order to operate properly with the O / S. In addition, the methods implemented according to the teachings of the present invention can be expressed as: (a) an object-oriented programming language with data and method classes; or (b) a procedural programming language with routines, subroutines and / or functions, such as but not limited to C, C++, Pascal, Basic, Fortran, Cobol, Perl, Java, and Ada.

[0184] When the method is implemented in software, it should be noted that such software can be stored on any computer-readable medium for use or in combination with any computer-related system or method. In the context of the present invention, a computer-readable medium is an electronic, magnetic, optical or other physical device or apparatus that can contain or store a computer program for use or in combination with a computer-related system or method. Such an arrangement can be embodied in any computer-readable medium used or in combination with an instruction execution system, device or apparatus such as a computer-based system, a processor-containing system or other system, which can obtain instructions from the instruction execution system, device or apparatus and execute instructions. In the context of the present invention, "computer-readable medium" can be any device that can store, communicate, propagate or transmit a program for use or in combination with an instruction execution system, device or apparatus. Computer-readable media can be, for example, but not limited to, electronic, magnetic, optical, electromagnetic, infrared or semiconductor systems, devices, devices or propagation media. As will be understood by those of ordinary skill in the art, any process description or block diagram in the accompanying drawings should be understood to represent a module, code segment or code portion, which includes one or more executable instructions for implementing a specific logical function or step in the process.

[0185] The above detailed description of the embodiments of the present invention is not intended to be exhaustive, nor is it intended to limit the present invention to the exact form disclosed. Although the specific examples of the present invention are described above for illustrative purposes, it will be appreciated by those skilled in the relevant art that various modifications may be made within the scope of the present invention. For example, although the processes and block diagrams have been shown in a particular order, different implementations may implement routes or adopt systems with block diagrams in alternative orders, and certain processes or block diagrams may be deleted, supplemented, added, moved, separated, combined and / or modified to provide different combinations or sub-combinations. Each of these processes or block diagrams may be implemented in a variety of alternative ways. Moreover, although processes or block diagrams are sometimes shown as being implemented in sequence, these processes or block diagrams may be implemented or implemented in parallel instead, or may be implemented at different times. As a method of increasing production capacity and reducing processing requirements, the results of processes or block diagrams may also be stored in non-persistent storage.

Claims

1. A method for treating wastewater, the method comprising the following steps: Provide nano bubble generator, providing therein a liquid and a biogas, the biogas comprising methane and at least one additional constituent gas component; generating an electric field using electrodes in the vicinity of the nanobubble generator to generate nanobubbles of the first gas component of the biogas and a purified methane gas component of the biogas, wherein the electrodes are not in direct electrical contact with the liquid to prevent electrolysis from occurring within the nanobubble generator; Outputting the purified methane gas component of the biogas from the nanobubble generator via a first outlet; providing a container for receiving wastewater and nanobubbles of the first gas component; directing the wastewater and the first gas component to the container; Wherein directing the first gas component to the container comprises: controllably releasing nanobubbles of the first gas component from a volume; reducing the temperature of the contents of the container from a first temperature to a second temperature to promote formation of a clathrate hydrate comprising the wastewater and the first gas component; increasing the temperature of the contents of the container relative to the second temperature to promote melting of the clathrate hydrate; and Clean water and / or the first gas component are removed from the container.

2. The method for treating wastewater according to claim 1, wherein controllably releasing nanobubbles of the first gas component comprises: A signal is applied to the liquid storing the nanobubbles.

3. The method for treating wastewater according to claim 2, wherein the signal comprises at least one of a sound signal or an electromagnetic signal.

4. The method for treating wastewater according to claim 1, further comprising: The residue was removed from the container.

5. The method for treating wastewater according to claim 1, further comprising: A second gas component of the gas is removed from the nanobubble generator. 6 . The method for treating wastewater according to claim 1 , wherein the first gas component of the biogas comprises carbon dioxide or carbon monoxide.

7. A system for treating wastewater, the system comprising: a nanobubble generator having therein a liquid and biogas, wherein the biogas comprises methane and at least one additional constituent gas component; an electrode for generating an electric field in the vicinity of the nanobubble generator to generate nanobubbles of the first gas component of the biogas and a purified methane gas component of the biogas, wherein the electrode and the first liquid are not in direct electrical contact to prevent electrolysis from occurring within the nanobubble generator; a first outlet configured to output a purified methane gas component of the biogas from the nanobubble generator; a container for receiving wastewater and the first gas component; means for directing said wastewater to said container; A temperature control device, wherein the temperature control device is constructed as follows: reducing the temperature of the contents of the container from a first temperature to a second temperature to promote formation of a clathrate hydrate comprising the wastewater and the first gas component; and increasing the temperature of the container relative to the second temperature to promote melting of the clathrate hydrate; and Means for removing clean water and / or said first gas component from said container.

8. The system for treating wastewater of claim 7, further comprising means for controllably releasing nanobubbles of the first gas component from the volumetric region.

9. The system for treating wastewater according to claim 8, wherein the means for controllably releasing nanobubbles of the first gas component is constructed in such a manner as to apply a signal to a liquid storing the nanobubbles.

10. The system for treating wastewater according to claim 9, wherein the signal comprises at least one of an acoustic signal or an electromagnetic signal.

11. The system for treating wastewater according to claim 7, further comprising means for removing residue from the container.

12. The system for treating wastewater of claim 7, further comprising means for removing a second gas component from the nanobubble generator.

13. The system for treating wastewater according to claim 7, wherein the first gas component of the biogas comprises carbon dioxide or carbon monoxide.

14. A system for processing a multi-component mixture, the system comprising: a nanophase generator for generating nanobubbles or nanodroplets, and a liquid and a first medium therein, wherein the first medium comprises biogas, the biogas comprising methane and at least one additional constituent gas component; an electrode for generating an electric field in the vicinity of the nanophase generator to generate nanobubbles or nanodroplets of a first medium and a purified methane gas component of the biogas, wherein the electrode and the liquid are not in direct electrical contact to prevent electrolysis from occurring within the nanophase generator; a first outlet configured to output a purified methane gas component of the biogas from the nanophase generator; a container for receiving the first medium and the second medium; a source for supplying the second medium to the container; A temperature control device for controlling the temperature of the contents of the container, wherein the temperature control device is configured to control the temperature of the contents of the container in a manner to promote the formation of a hydrate comprising the first medium and the second medium, and wherein the temperature control device is configured to control the temperature in a manner to promote melting of the hydrate to provide a first treated medium and a second treated medium.

15. The system for processing a multi-component mixture of claim 14, wherein the hydrate formed in the container is a clathrate hydrate.

16. The system for processing a multi-component mixture of claim 14, further comprising an agitation device for controllably releasing the nanobubbles from the volume.

17. The system for processing a multi-component mixture according to claim 16, wherein the agitation device comprises an acoustic signal or an electromagnetic signal.

18. The system for processing a multi-component mixture of claim 14, further comprising at least one outlet for directing one or more of the first processed medium, the second processed medium, or the particulate matter out of the container.

19. The system for treating a multi-component mixture according to claim 14, wherein the biogas of the first medium further comprises a carbon dioxide gas component.

20. The system for treating a multi-component mixture of claim 14, wherein the second medium comprises wastewater.

21. The system for treating a multi-component mixture of claim 15, wherein the clathrate hydrate is formed from carbon dioxide molecules and wastewater.

22. The system for processing a multi-component mixture of claim 14, wherein a source for providing the first medium is also a source for providing the second medium.

23. The system for processing a multi-component mixture of claim 22, wherein the source for providing the first medium and the second medium is an anaerobic digester.

24. The system for treating a multi-component mixture of claim 14, wherein one of the first treatment medium and the second treatment medium comprises a purified water component.

25. The system for processing a multi-component mixture of claim 14, wherein the source of the gas is a flue.

26. The system for processing a multi-component mixture of claim 14, wherein the gas comprises O2 or N2.

27. The system for treating a multi-component mixture of claim 20, wherein the second medium comprises petroleum.

28. The system for processing a multi-component mixture of claim 14, wherein the gas comprises atmospheric air.

29. A method for treating a multi-component mixture, the method comprising: providing a nanophase generator for generating nanobubbles or nanodroplets, and providing a liquid and a first medium therein, wherein the first medium comprises biogas, the biogas comprising methane and at least one additional constituent gas component; generating an electric field using electrodes in the vicinity of the nanophase generator to generate nanobubbles or nanodroplets of a first medium and a purified methane gas component of the biogas, wherein the electrodes and the liquid are not in direct electrical contact to prevent electrolysis from occurring within the nanophase generator; outputting the purified methane gas component of the biogas from the nanophase generator via a first outlet; controllably releasing the nanobubbles or nanodroplets from the nanophase generator into a container; providing a second medium to the container; controlling the temperature of the contents of the container to promote formation of a hydrate comprising the first medium and the second medium; as well as The temperature of the contents of the container is controlled to promote melting of the hydrate, thereby providing a first treated medium and a second treated medium.

30. A method for treating a multi-component mixture according to claim 29, wherein the hydrate formed is a clathrate hydrate.

31. The method of processing a multi-component mixture of claim 29, wherein an acoustic signal or an electromagnetic signal is applied to controllably release the nanobubbles from the volume of the nanophase generator.

32. The method of processing a multi-component mixture according to claim 29, further comprising: One or more of the first processed medium, the second processed medium, or particulate matter is directed from the container.

33. The method for treating a multi-component mixture according to claim 29, wherein the biogas of the first medium further comprises a carbon dioxide gas component.

34. The method for treating a multi-component mixture of claim 29, wherein the second medium comprises wastewater.

35. The method for treating a multi-component mixture according to claim 30, wherein the clathrate hydrate is formed from carbon dioxide molecules and wastewater.

36. The method for processing a multi-component mixture according to claim 29, wherein the source for providing the first medium is also the source for providing the second medium.

37. The method for treating a multi-component mixture of claim 29, wherein the source for providing the first medium and the second medium is an anaerobic digester.

38. The method for treating a multi-component mixture of claim 29, wherein one of the first treated medium and the second treated medium comprises a purified water component.

39. The method for processing a multi-component mixture according to claim 29, wherein the gas comprises O2 or N2.

40. The method for treating a multi-component mixture of claim 29, wherein the second medium comprises petroleum.

41. The method of processing a multi-component mixture of claim 29, wherein the gas comprises atmospheric air.

42. The method of processing a multi-component mixture according to claim 29, further comprising: Nanophases are developed for differential absorption of multicomponent gas mixtures in the gas phase and / or dissolved in an immiscible liquid phase.

43. The method of claim 42, wherein the general gas-liquid equilibrium constant is of the form i =H i x i (where H i is Henry's law constant, HLC) can be used Instead, is the enhanced actual HLC due to the additional accommodation of the nanophase.

44. The method of claim 42, wherein the surface area / volume ratio is increased in the nanophase.

45. The method of claim 42, wherein the nanophase is used in a distillation application.

46. ​​The method of claim 29, further comprising: Removal of gaseous components from flue gases.

47. The method of claim 46, further comprising: Hydrophobic or carbon nanotube filtration for nanotube generated gases.

48. The method of claim 29, further comprising: Direct Air Capture (DAC).

49. The method of claim 36, wherein for a mixture of immiscible liquids, the liquid-liquid equilibrium-partition relationship is of the form x i,k =K i,j,k x i,j Available Instead, Where K i,j,k is the liquid-liquid partition coefficient of species j relative to species k in liquid phase i, in is the enhanced actual partition coefficient due to the additional preferential accommodation in one phase.

50. The method of claim 36, wherein the solid-liquid equilibrium-partition relationship is of the form k =K j,k x j Available Instead, Where K j,k is the solid-liquid partition coefficient of species j in the solid phase relative to species k, in is the enhanced actual partition coefficient due to the additional preferential accommodation in the liquid phase as nanobubbles or nanodroplets.

51. The method of claim 37, wherein excess H2 is introduced into the anaerobic digester in the form of nanobubbles.

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